What is the objective? Maximize the data rate number of bits that the system can transmit in a unit of time -within an acceptable bit error rate Why there could be bit errors? The signal received by the receiver is different from the signal sent from the sender Usually, if data rate becomes higher, it is more difficult for the receiver to recognize the signal higher data rate results in higher bit error rate In order to achieve high data rate with low bit error rate, we need to study the principle of data communications 55 What is the objective? • Maximize the data rate: number of bits that the system can transmit in a unit of time —within an acceptable bit error rate • Why there could be bit errors? —The signal received by the receiver is different from the signal sent from the sender • Usually, if data rate becomes higher, it is more difficult for the receiver to recognize the signal —higher data rate results in higher bit error rate • In order to achieve high data rate with low bit error rate, we need to study the principle of data communications